Joint International Conference on Long-term Experiments ...

Maize grain yield t ha -1
Maize grain yield t ha -1
Maize grain yield t ha -1
18
16
14
12
10
18
16
14
12
10
8
6
4
2
0
8
6
4
2
0
18
16
14
12
10
8
6
4
2
0
Optimum values
of all factors
Minimum
values of all
factors
0 2 4 6 8 10 12
Optimum values
of all factors
0 2 4 6 8 10 12
Optimum values
of all factors
Minimum level
of fertilisation
Minimum for
genotype
0 2 4 6 8 10 12
Environmental index t ha -1
Figure 3. Yield response of maize for minimum levels of production factors vs.
optimum level of all factors in comparision to the environmental index in the longterm
experiment (1960-2001)
26
18
16
14
12
10
8
6
4
2
0
18
16
14
12
10
8
6
4
2
0
18
16
14
12
10
8
6
4
2
0
Optimum values
of all factors
Minimum depth of
soil cultivation
0 2 4 6 8 10 12
Optimum values of
all factors
Minimum plant
density
0 2 4 6 8 10 12
Optimum values
of all factors
Minimum weed
control
0 2 4 6 8 10 12
Environmental index t ha -1